Re: New Find In Arizona

[Tom Holtz <tholtz@geochange.er.usgs.gov>]

>The folwg news story is quoted from ''The Arizona Daily Star'',
>Tucson, 19 Feb 95:
>Dinosaur bones found near Sonoita
[deleted]
>     Ron Ratkevich, a paleontologist with Tucson's Arizona-Sonora Desert
>Museum, said the site has at least 50 bones which apparently date from
>100 million to 120 million years ago in the early Cretaceous Period
>during which few dinosaur remains have been found anywhere.

Not true!  Although fewer total species are known from any one locality
this interval than in the Oxfordian-Tithonian or the
Campanian-Maastrichtian, sites from western, central, and eastern U.S.A.,
Argentina, western and central Europe, northern and central Africa, and
Australia from this time (the Aptian-Albian).

>     One set of bones protruding from a slab of sandstone includes an
>animal's pelvis, ribs, shoulder blade and neck vertebrae, he said.
>Ratkevich said the dinosaur's skull may be inside the rock.
>     "This is likely a new species of dinosaur," Ratkevich said,
>adding that skulls are rarely found.
>     Ratkevich said the animal apparently was between a horse and an
>elephant in size with hips similar to those of long-necked dinosaurs
>known as sauropods.
>     Ratkevich, who hopes to begin excavation work next week, said
>other bones are scattered about the site.  He said they range in size
>from that of a human thumb to that of two fists.  One appears to be
>a claw, he said.
>     Another fossil appears to be a smoothed "stomach stone" of the
>kind that helped plant-eating dinosaurs digest their food, he said.
>     "We've just touched the tip of the iceberg," Ratkevich said.
>"It looks like all of this could lead to something very remarkable."
>     Nelson said he and Thompson were looking for petrified wood
>when they saw what appeared to be fossilized bone fragments that
>have washed down from higher ground.
>     "We followed the bones up the slope and then we found the
>skeleton," said Nelson, an amateur fossil hunter.
>     The pelvic bone, he said, was protruding from the ground
>"like a lightning rod."

It sounds like it could concievably be a Pleurocoelus/Astrodon (small North
American brachiosaurid).  It's the right age for one, although there may
have been more than one genus of sauropod in North America at this time.

                                
Thomas R. Holtz, Jr.                                   
tholtz@geochange.er.usgs.gov
Vertebrate Paleontologist in Exile                  Phone:      703-648-5280
U.S. Geological Survey                                FAX:      703-648-5420
Branch of Paleontology & Stratigraphy
MS 970 National Center
Reston, VA  22092
U.S.A.